On 12/30/2010 11:20 AM, Sheng Yang wrote:
On Thursday 30 December 2010 17:14:23 Avi Kivity wrote: > On 12/30/2010 11:05 AM, Sheng Yang wrote: > > > > if (!(cr0& X86_CR0_PG)) { > > > > > > > > /* From paging/starting to nonpaging */ > > > > vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, > > > > > > > > @@ -1937,11 +1936,8 @@ static void > > > > ept_update_paging_mode_cr0(unsigned long *hw_cr0, > > > > > > > > vmcs_read32(CPU_BASED_VM_EXEC_CONTROL)& > > > > > > > > ~(CPU_BASED_CR3_LOAD_EXITING | > > > > > > > > CPU_BASED_CR3_STORE_EXITING)); > > > > > > > > - /* Must fetch cr3 before updating cr0 */ > > > > - cr3 = kvm_read_cr3(vcpu); > > > > > > > > vcpu->arch.cr0 = cr0; > > > > vmx_set_cr4(vcpu, kvm_read_cr4(vcpu)); > > > > > > > > - vmx_set_cr3(vcpu, cr3); > > > > > > This is indeed bogus. But what ensures that we'll have the correct > > > GUEST_CR3 after enabling paging? > > > > In fact I don't understand why we need this line. All modification is for > > CR3 reading, why we need to set hardware CR3 again? It should be the > > same as when we don't have CR3 accessor I think. > > when cr0.pg=0 then we set GUEST_CR3=identity_pagetable. We don't want > that when we we switch to paging mode.I think kvm_mmu_reset_context() in kvm_set_cr0() should cover this?
I looked at it but missed it. kvm_mmu_reset_context() doesn't actually do this, but it does schedule a kvm_mmu_load() which will call vmx_set_cr3().
Thanks, I'll apply your v2 now. -- error compiling committee.c: too many arguments to function -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
